package com.atguigu.gulimall.ware.service.impl;

import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.to.mq.OrderTo;
import com.atguigu.common.to.mq.StockDetailTo;
import com.atguigu.common.to.mq.StockLockedTo;
import com.atguigu.common.utils.R;
import com.atguigu.gulimall.ware.entity.WareOrderTaskDetailEntity;
import com.atguigu.gulimall.ware.entity.WareOrderTaskEntity;
import com.atguigu.gulimall.ware.exception.NoStockException;
import com.atguigu.gulimall.ware.feign.OrderFeignService;
import com.atguigu.gulimall.ware.feign.ProductFeignService;
import com.atguigu.gulimall.ware.service.WareOrderTaskDetailService;
import com.atguigu.gulimall.ware.service.WareOrderTaskService;
import com.atguigu.gulimall.ware.vo.*;
import com.baomidou.mybatisplus.core.toolkit.StringUtils;
import com.rabbitmq.client.Channel;
import com.sun.org.apache.xpath.internal.operations.Bool;
import lombok.Data;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitHandler;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.ware.dao.WareSkuDao;
import com.atguigu.gulimall.ware.entity.WareSkuEntity;
import com.atguigu.gulimall.ware.service.WareSkuService;
import org.springframework.transaction.annotation.Transactional;


@Service("wareSkuService")
public class WareSkuServiceImpl extends ServiceImpl<WareSkuDao, WareSkuEntity> implements WareSkuService {

    @Autowired
    WareSkuDao wareSkuDao;

    @Autowired
    ProductFeignService productFeignService;

    @Autowired
    RabbitTemplate rabbitTemplate;

    @Autowired
    WareOrderTaskService orderTaskService;

    @Autowired
    WareOrderTaskDetailService orderTaskDetailService;

    @Autowired
    OrderFeignService orderFeignService;


    // TODO: 自动关单有问题
    private void unLockStock(Long skuId, Long wareId, Integer num, Long taskDetailId) {
        // 库存解锁
        wareSkuDao.unlockStock(skuId, wareId, num);
        // 更新库存工作单的状态
        WareOrderTaskDetailEntity entity = new WareOrderTaskDetailEntity();
        entity.setLockStatus(2);    // 已解锁
        entity.setId(taskDetailId);
        orderTaskDetailService.updateById(entity);

    }

    @Override
    public PageUtils queryPage(Map<String, Object> params) {

        QueryWrapper<WareSkuEntity> wrapper = new QueryWrapper<>();

        String skuId = (String) params.get("skuId");
        if (!StringUtils.isEmpty(skuId)) {
            wrapper.eq("sku_id", skuId);
        }

        String wareId = (String) params.get("wareId");
        if (!StringUtils.isEmpty(wareId)) {
            wrapper.eq("sku_id", skuId);
        }

        IPage<WareSkuEntity> page = this.page(
                new Query<WareSkuEntity>().getPage(params),
                wrapper
        );

        return new PageUtils(page);
    }

    @Override
    public void addStock(Long skuId, Long wareId, Integer skuNum) {

        // 1. 判断如果还没有这个库存记录新增
        List<WareSkuEntity> entities = wareSkuDao.selectList(new QueryWrapper<WareSkuEntity>().eq("sku_id", skuId).eq("ware_id", wareId));
        if (entities == null || entities.size() == 0) {
            WareSkuEntity skuEntity = new WareSkuEntity();
            skuEntity.setSkuId(skuId);
            skuEntity.setStock(skuNum);
            skuEntity.setWareId(wareId);
            skuEntity.setStockLocked(0);
            // TODO 远程查询sku的名字, 如果失败,整个事务无需回滚
            // 1. 自己catch掉异常
            // TODO 还可以用什么办法让异常出现之后不回滚
            try {
                R info = productFeignService.info(skuId);
                Map<String, Object> data = (Map<String, Object>) info.get("skuInfo");
                if (info.getCode() == 0) {
                    skuEntity.setSkuName((String) data.get("skuName"));
                }
            } catch (Exception e) {

            }

            wareSkuDao.insert(skuEntity);
        } else {
            wareSkuDao.addStock(skuId, wareId, skuNum);
        }

    }

    @Override
    public List<SkuHasStockVo> getSkusHasStock(List<Long> skuIds) {

        List<SkuHasStockVo> collect = skuIds.stream().map(skuId -> {
            SkuHasStockVo vo = new SkuHasStockVo();

            // 查询当前的sku总库存
            Long count = baseMapper.getSkuStock(skuId);
            vo.setSkuId(skuId);
            vo.setHasStock(count != null && count > 0);
            return vo;
        }).collect(Collectors.toList());
        return collect;

    }

    /**
     * 为某个订单锁定库存
     * rollbackFor = NoStockException.class
     * 默认只要是运行时异常都会回滚
     * <p>
     * 库存解锁的场景:
     * 1) 下订单成功, 订单过期没有支付, 被系统自动取消, 或者被用户手动取消, 都要解锁库存
     * 2) 下订单成功, 库存锁定成功, 接下来的业务调用失败, 导致订单回滚, 之前锁定的库存就要回滚, 自动解锁
     *
     * @param vo
     * @return
     */
    @Transactional(rollbackFor = NoStockException.class)
    @Override
    public Boolean orderLockStock(WareSkuLockVo vo) {
        /**
         * 保存库存工作单的详情
         * 追溯
         */
        WareOrderTaskEntity taskEntity = new WareOrderTaskEntity();
        taskEntity.setOrderSn(vo.getOrderSn());
        orderTaskService.save(taskEntity);


        // 找到每个商品再哪个仓库有库存
        List<OrderItemVo> locks = vo.getLocks();
        List<SkuWareHasStock> collect = locks.stream().map(item -> {
            SkuWareHasStock stock = new SkuWareHasStock();
            Long skuId = item.getSkuId();
            stock.setSkuId(skuId);
            stock.setNum(item.getCount());
            // 查询这个商品在哪里有库存
            List<Long> wareIds = wareSkuDao.listWareIdHasSkuStock(skuId);
            stock.setWareId(wareIds);
            return stock;
        }).collect(Collectors.toList());

        // 2. 锁定库存
        for (SkuWareHasStock hasStock : collect) {
            Boolean skuStocked = false;
            Long skuId = hasStock.getSkuId();
            List<Long> wareIds = hasStock.getWareId();
            if (wareIds == null || wareIds.size() == 0) {
                throw new NoStockException(skuId);
            }
            // 1. 如果每一个商品都锁定成功, 将当前商品锁定了几件的工作单记录发送给MQ
            // 2. 锁定失败. 前面保存的工作单信息就回滚了. 发出去的消息即使要解锁记录, 由于数据库查不到id, 所以就不用解锁了
            //
            for (Long wareId : wareIds) {
                Long count = wareSkuDao.lockWareSku(skuId, wareId, hasStock.getNum());
                if (count == 0) {
                    skuStocked = false;
                } else {
                    // TODO: 告诉MQ, 库存锁定成功
                    WareOrderTaskDetailEntity detailEntity = new WareOrderTaskDetailEntity(null, skuId, "", hasStock.getNum(), taskEntity.getId(), wareId, 1);
                    orderTaskDetailService.save(detailEntity);
                    StockLockedTo lockedTo = new StockLockedTo();
                    lockedTo.setId(taskEntity.getId());
                    StockDetailTo stockDetailTo = new StockDetailTo();
                    BeanUtils.copyProperties(detailEntity, stockDetailTo);
                    // 只发id不行, 防止回滚以后找不到数据
                    lockedTo.setDetailTo(stockDetailTo);
                    rabbitTemplate.convertAndSend("stock-event-exchange", "stock.locked", lockedTo);
                    skuStocked = true;
                    break;
                }
            }
            if (!skuStocked) {
                // 当前商品所有仓库都没有锁住
                throw new NoStockException(skuId);
            }

        }


        return true;

    }

    @Override
    public void unlockStock(StockLockedTo to) {


        StockDetailTo detail = to.getDetailTo();
        Long detailId = detail.getId();
        /**
         * 解锁:
         * 1. 查询数据库关于这个订单的锁定库存信息
         *      有: 库存锁定成功:
         *          解锁: 订单情况
         *              1. 没有订单, 必须解锁
         *              2. 有订单, 订单状态
         *                  已取消: 解锁库存
         *                  没取消: 不能解锁
         *      没有: 库存锁定失败了, 库存回滚,导致没有, 无需解锁
         */
        WareOrderTaskDetailEntity byId = orderTaskDetailService.getById(detailId);
        if (byId != null) {
            // 解锁
            Long id = to.getId();       // 库存工作单的id
            WareOrderTaskEntity taskEntity = orderTaskService.getById(id);
            String orderSn = taskEntity.getOrderSn();       // 根据订单号查询订单的状态
            // 本身这里是没有登录的, 因为远程调用接口的源头时MQ监听器, 不是用户
            R r = orderFeignService.getOrderStatus(orderSn);
            if (r.getCode() == 0) {
                // 订单数据返回成功
                OrderVo data = r.getData(new TypeReference<OrderVo>() {
                });
                if (data == null || data.getStatus() == 4) {
                    // 订单被取消, 才能解锁库存 || 订单不存在
                    if(byId.getLockStatus() == 1) {
                        // 当前库存工作单详情已锁定, 状态为1
                        unLockStock(detail.getSkuId(), detail.getWareId(), detail.getSkuNum(), detailId);
                    }
                }

            } else {
                // 消息拒绝以后重新放入队列里面, 让别人继续消费解锁
                throw new RuntimeException("远程服务失败");
            }

        }

    }

    /**
     * 防止订单服务卡顿, 导致订单状态一致无法更改, 库存消息优先到期, 查订单状态为新建, 导致误判
     * @param orderTo
     */
    @Transactional
    @Override
    public void unlockStock(OrderTo orderTo) {

        String orderSn = orderTo.getOrderSn();
        // 查一下最新的库存解锁状态状态, 防止重复解锁库存
        WareOrderTaskEntity task = orderTaskService.getOrderTaskByOrderSn(orderSn);
        Long id = task.getId();
        // 按照库存工作单, 找到所有没有解锁的库存, 进行解锁
        List<WareOrderTaskDetailEntity> entities = orderTaskDetailService.list(new QueryWrapper<WareOrderTaskDetailEntity>()
                .eq("task_id", id)
                .eq("lock_status", 1));

        for(WareOrderTaskDetailEntity entity : entities) {
            unLockStock(entity.getSkuId(), entity.getWareId(), entity.getSkuNum(), entity.getId());
        }


    }


    @Data
    class SkuWareHasStock {
        private Long skuId;
        private Integer num;
        private List<Long> wareId;
    }

}